Coronavirus Thread

[volvolugnut]

I started to wonder if there is a relationship between percent vaccinated for Covid-19 and the infection growth rate of a state. The entire country now has about half the people vaccinated. I have enough data to make a rough study of this question.

The percentage of people vaccinated in a state plus the percentage of the state that have previously had Covid-19 has been reported in previous posts. I have been reporting the daily growth rate of the states for many months. To make the study, I looked at the top 5 states and bottom 5 states with the combined vaccination and infection totals. Although these states change from week to week, the states are quite consistent and I used the states that have repeatedly made the top and bottom lists.

For the comparison of change in growth rate, I looked at two periods. The first period was February 28 to March 20, 2021. The second period started two weeks after the first period ended for April 4 to April 24, 2021. I intentionally avoided the period when much of the country had severe winter storms which delayed vaccinations. I selected a 2 week gap to separate the periods and highlight the differences if any. During the first and second periods, the number of new cases and active cases in the US were relatively flat. The top 5 states are Alaska, New Mexico, North Dakota, Rhode Island, and South Dakota. The bottom 5 states are Alabama, District of Columbia, Georgia, Mississippi, and Oregon.

I averaged the growth rates for each day for each state within the time period. In some states (Alaska and Oregon) the growth rate was zero for several days in the first period and these days were removed from the average calculation. After both periods were averaged for the top and bottom 5 states, the second period was subtracted from the first period. If the difference was positive, the study would show the improvement of growth rate after vaccination.

Actual results are inconclusive. Some of the states showed improvement, but other states did not improve. Any change differences were minimal.

The answer to my study is not clear at this time. The time period of the study included a change in combined vaccination/ infection percentage from about 25 to 50%. This may not be great enough difference and the final vaccination percentage may not be enough to obtain any level of herd immunity. However, I am not discouraged and expect the country will eventually see improvements.

Sources include Worldometer and New York Times. Any errors or misrepresentations are my own.

volvolugnut

[volvolugnut]

More statistics on US states and COVID-19 growth rates. My raw information is from Worldometer. Any errors or misrepresentations are my own.

These tables show all available US states and territories and the COVID-19 data for the last 5 days. I have sorted the states alphabetically and added growth rates for last several days for all states with ranking of each day. Of course, this information changes daily. I have presented the table in two parts because of the screen shot, but it is actually one table in Excel.

Again, results change daily.

State growth rates for April 28, 2020. All information is based on reported information and actual results may be different.

For your information, the top 5 states or territories yesterday in growth rate (the worst containment) are: Wyoming (0.282) with 57,999 cases, Montana (0.212) with 108,489 cases, Guam (0.176) with 7951 cases, Arkansas (0.153) with 335,289 cases, and North Dakota (0.149) with 107,154 cases. Wyoming has been in top 5 list for 107 of last 220 days. Montana has been in top 5 list for 57 of last 120 days. Guam has been in top 5 list for 15 of last 26 days. Arkansas has been in top 5 list for 112 of last 251 days. North Dakota has been in top 5 list for 190 of last 300 days.

Hawaii, Louisiana, Maine, and South Carolina did not report active cases. Several states have stopped posting new case and new death numbers. I will back calculate where possible.

A column on the right shows the current growth rate divided by the 5 day moving average. Alaska, Mississippi, North Carolina, Rhode Island, Tennessee, Texas, US Virgin Islands, and US Military were over 2.0 yesterday (red highlight). Arkansas, Missouri, Montana, Nevada, New Mexico, Oklahoma, South Dakota, Wyoming, and Navajo Nation were over 1.5 yesterday (yellow highlight). This is an early warning of higher growth rate in states. Many states now do not report every day making this measure more variable for those states.

My calculated growth rate for USA is 0.00830 for yesterday, up from previous day of 0.00764. This is not population or case number weighted.

Daily active case counts have a notable decline over the last several weeks. The number of active cases have dropped about 24% since the peak. This decrease in active case numbers had not been seen since I started recording information in February 2020. However, the last couple weeks have not extended this decrease in active case counts.

volvolugnut

[volvolugnut]

More statistics on US states and COVID-19 growth rates. My raw information is from Worldometer. Any errors or misrepresentations are my own.

These tables show all available US states and territories and the COVID-19 data for the last 5 days. I have sorted the states alphabetically and added growth rates for last several days for all states with ranking of each day. Of course, this information changes daily. I have presented the table in two parts because of the screen shot, but it is actually one table in Excel.

Again, results change daily.

State growth rates for April 29, 2020. All information is based on reported information and actual results may be different.

For your information, the top 5 states or territories yesterday in growth rate (the worst containment) are: Montana (0.175) with 108,663 cases, Minnesota (0.138) with 573,938 cases, Wyoming (0.135) with 58,069 cases, North Dakota (0.133) with 107,298 cases, and Arkansas (0.122) with 335,529 cases. Montana has been in top 5 list for 58 of last 121 days. Minnesota has been in top 5 list for 197 of last 267 days. Wyoming has been in top 5 list for 108 of last 221 days. North Dakota has been in top 5 list for 191 of last 301 days. Arkansas has been in top 5 list for 113 of last 252 days.

Hawaii, Louisiana, Maine, and South Carolina did not report active cases. Several states have stopped posting new case and new death numbers. I will back calculate where possible.

A column on the right shows the current growth rate divided by the 5 day moving average. No areas were over 2.0 yesterday (red highlight). Colorado, North Carolina, Oklahoma, Vermont, and Veterans Affairs were over 1.5 yesterday (yellow highlight). This is an early warning of higher growth rate in states. Many states now do not report every day making this measure more variable for those states.

My calculated growth rate for USA is 0.00870 for yesterday, up from previous day of 0.00830. This is not population or case number weighted.

Daily active case counts have a notable decline over the last several weeks. The number of active cases have dropped about 24% since the peak. This decrease in active case numbers had not been seen since I started recording information in February 2020. However, the last couple weeks have not extended this decrease in active case counts.

Volvolugnut

[volvolugnut]

More statistics on US states and COVID-19 growth rates. My raw information is from Worldometer. Any errors or misrepresentations are my own.

These tables show all available US states and territories and the COVID-19 data for the last 5 days. I have sorted the states alphabetically and added growth rates for last several days for all states with ranking of each day. Of course, this information changes daily. I have presented the table in two parts because of the screen shot, but it is actually one table in Excel.

Again, results change daily.

State growth rates for April 30, 2020. All information is based on reported information and actual results may be different.

For your information, the top 5 states or territories yesterday in growth rate (the worst containment) are: US Virgin Islands (0.300) with 3116 cases, North Dakota (0.160) with 107,473 cases, Montana (0.152) with 108,817 cases, Wyoming (0.151) with 58,142 cases, and Minnesota (0.128) with 575,812 cases. North Dakota has been in top 5 list for 192 of last 302 days. Montana has been in top 5 list for 59 of last 122 days. Wyoming has been in top 5 list for 109 of last 222 days. Minnesota has been in top 5 list for 198 of last 268 days.

Hawaii, Louisiana, Maine, and South Carolina did not report active cases. Several states have stopped posting new case and new death numbers. I will back calculate where possible.

A column on the right shows the current growth rate divided by the 5 day moving average. US Virgin Islands were over 2.0 yesterday (red highlight). Delaware, and Vermont were over 1.5 yesterday (yellow highlight). This is an early warning of higher growth rate in states. Many states now do not report every day making this measure more variable for those states.

My calculated growth rate for USA is 0.00879 for yesterday, up from previous day of 0.00870. This is not population or case number weighted.

Daily active case counts have a notable decline over the last several weeks. The number of active cases have dropped about 24% since the peak. This decrease in active case numbers had not been seen since I started recording information in February 2020. However, the last couple weeks have not extended this decrease in active case counts.

Volvolugnut

[volvolugnut]

More statistics on US states and COVID-19 growth rates. My raw information is from Worldometer. Any errors or misrepresentations are my own.

These tables show all available US states and territories and the COVID-19 data for the last 5 days. I have sorted the states alphabetically and added growth rates for last several days for all states with ranking of each day. Of course, this information changes daily. I have presented the table in two parts because of the screen shot, but it is actually one table in Excel.

Again, results change daily.

State growth rates for May 1, 2020. All information is based on reported information and actual results may be different.

For your information, the top 5 states or territories yesterday in growth rate (the worst containment) are: US Virgin Islands (0.200) with 3125 cases, Montana (0.161) with 108,985 cases, North Dakota (0.150) with 107,639 cases, Guam (0.124) with 7975 cases, and Arkansas (0.120) with 335,968 cases. Montana has been in top 5 list for 60 of last 123 days. North Dakota has been in top 5 list for 193 of last 303 days. Guam has been in top 5 list for 16 of last 29 days. Arkansas has been in top 5 list for 114 of last 254 days.

Hawaii, Louisiana, Maine, and South Carolina did not report active cases. Several states have stopped posting new case and new death numbers. I will back calculate where possible.

A column on the right shows the current growth rate divided by the 5 day moving average. No areas were over 2.0 yesterday (red highlight). US Virgin Islands was over 1.5 yesterday (yellow highlight). This is an early warning of higher growth rate in states. Many states now do not report every day making this measure more variable for those states.

My calculated growth rate for USA is 0.00618 for yesterday, down from previous day of 0.00879. This is not population or case number weighted.

Daily active case counts have a notable decline over the last couple months. The number of active cases have dropped about 25% since the peak. This decrease in active case numbers had not been seen since I started recording information in February 2020.

Volvolugnut

[volvolugnut]

More statistics on US states and COVID-19 growth rates. My raw information is from Worldometer. Any errors or misrepresentations are my own.


To give some context to these changes, I have calculated the average growth rate for each week back to April. The growth rate is calculated as the number of new cases each day divided by the number of active cases for the previous day. There is a typical weekly pattern of rising cases each week and falling case numbers on the weekends. I have calculated the 7 day average of the growth rate for Saturday to Friday of each week.

Using the 7 day growth rate, a calculation can be made of the number of days for the new cases to double. This calculation uses (1+Growth Rate) to the exponential of 1/X and solved for when this equation equals 2 (doubling of new cases). Variable X is the number of days to double the new cases count. I have made this calculation using 14 day and 21 day growth rate averages as well.

A graph using the average for 7, 14, and 21 days and showing the days to double new case counts for April to middle of November is below. Another graph shows the 7 day average new virus cases counts for the same period.

Inspection of the graphs show that when the line for days to double becomes flat, there may soon be a decline or increase to the count of new cases. This has happened three times since April. When the slope of the line for doubling is steep, either going up or down, there is unlikely to be a change soon in the growth or decline in new cases.

The current lines for case doubling now shows some indication of going flat soon. I expect we will see the number of new virus cases continue to increase, but we may have a change of direction starting. Perhaps the changing recommendations for controlling the virus are beginning to have an impact.

There was an error in my original logic posted on November 14. During the upward slope periods of the Days to Double graph, the actual number of daily cases are declining. I reconsidered how to resolve this contradiction in logic.

I have added a new graph with a calculation of the slope of the new case numbers (current case count minus past case count divided by the number of days). The slope of a curve is the rate of change of the plotted line. If we were plotting velocity, the slope would be the acceleration. The slope is a better representation of the virus growth because the slope goes negative when the trend in cases starts going down.

volvolugnut

I have updated the graphs for the latest week (April 25 to May 1). The New Case Slope graph shows another decrease in the past week and stayed below zero for the second week since the end of March 2021. Days to Double graph has continued an increase for 7 day, 14 day, and 21 day lines in the past week. This continues a strong indication of improvement for all three measures. This week the new case count dropped below the levels for the middle of March 2021.

Stay safe out there.

volvolugnut

[volvolugnut]

More statistics on US states and COVID-19 growth rates. My raw information is from Worldometer. Any errors or misrepresentations are my own.

These tables show all available US states and territories and the COVID-19 data for the last 5 days. I have sorted the states alphabetically and added growth rates for last several days for all states with ranking of each day. Of course, this information changes daily. I have presented the table in two parts because of the screen shot, but it is actually one table in Excel.

Again, results change daily.

State growth rates for May 2, 2020. All information is based on reported information and actual results may be different.

For your information, the top 5 states or territories yesterday in growth rate (the worst containment) are: US Virgin Islands (0.265) with 3138 cases, Minnesota (0.113) with 579,235 cases, New Hampshire (0.087) with 95,377 cases, Arkansas (0.065) with 336,105 cases, and North Dakota (0.062) with 107,708 cases. US Virgin Islands has been in top 5 list for 6 of last 11 days. Minnesota has been in top 5 list for 199 of last 270 days. New Hampshire has been in top 5 list for 191 of last 304 days. Arkansas has been in top 5 list for 115 of last 255 days. North Dakota has been in top 5 list for 194 of last 304 days.

Hawaii, Louisiana, Maine, and South Carolina did not report active cases. Several states have stopped posting new case and new death numbers. I will back calculate where possible.

A column on the right shows the current growth rate divided by the 5 day moving average. District of Columbia was over 2.0 yesterday (red highlight). No areas were over 1.5 yesterday (yellow highlight). This is an early warning of higher growth rate in states. Many states now do not report every day making this measure more variable for those states.

My calculated growth rate for USA is 0.00453 for yesterday, down from previous day of 0.00618. This is not population or case number weighted.

Daily active case counts have a notable decline over the last couple months. The number of active cases have dropped about 25% since the peak. This decrease in active case numbers had not been seen since I started recording information in February 2020.

Volvolugnut

[volvolugnut]

More statistics on US states and COVID-19 growth rates. My raw information is from Worldometer. Any errors or misrepresentations are my own.

These tables show all available US states and territories and the COVID-19 data for the last 5 days. I have sorted the states alphabetically and added growth rates for last several days for all states with ranking of each day. Of course, this information changes daily. I have presented the table in two parts because of the screen shot, but it is actually one table in Excel.

Again, results change daily.

State growth rates for May 3, 2020. All information is based on reported information and actual results may be different.

For your information, the top 5 states or territories yesterday in growth rate (the worst containment) are: Wyoming (0.308) with 58,290 cases, Mississippi (0.114) with 312,400 cases, Guam (0.075) with 7989 cases, Minnesota (0.074) with 580,340 cases, and New Hampshire (0.058) with 95,506 cases. Wyoming has been in top 5 list for 110 of last 225 days. Guam has been in top 5 list for 17 of last 31 days. Minnesota has been in top 5 list for 200 of last 271 days. New Hampshire has been in top 5 list for 192 of last 305 days.

Hawaii, Louisiana, Maine, and South Carolina did not report active cases. Several states have stopped posting new case and new death numbers. I will back calculate where possible.

A column on the right shows the current growth rate divided by the 5 day moving average. Connecticut, Kansas, Mississippi, Wyoming, and US Military were over 2.0 yesterday (red highlight). Idaho, Washington, and Navajo Nation were over 1.5 yesterday (yellow highlight). This is an early warning of higher growth rate in states. Many states now do not report every day making this measure more variable for those states.

My calculated growth rate for USA is 0.00590 for yesterday, up from previous day of 0.00453. This is not population or case number weighted.

Daily active case counts have a notable decline over the last couple months. The number of active cases have dropped about 25% since the peak. This decrease in active case numbers had not been seen since I started recording information in February 2020.

Volvolugnut

[volvolugnut]

More statistics on US states and COVID-19 growth rates. My raw information is from Worldometer. Any errors or misrepresentations are my own.

These tables show all available US states and territories and the COVID-19 data for the last 5 days. I have sorted the states alphabetically and added growth rates for last several days for all states with ranking of each day. Of course, this information changes daily. I have presented the table in two parts because of the screen shot, but it is actually one table in Excel.

Again, results change daily.

State growth rates for May 4, 2020. All information is based on reported information and actual results may be different.

For your information, the top 5 states or territories yesterday in growth rate (the worst containment) are: US Virgin Islands (0.226) with 3152 cases, Montana (0.201) with 109,315 cases, Wyoming (0.175) with 58,367 cases, Guam (0.158) with 8004 cases, and South Dakota (0.151) with 122,974 cases. US Virgin Islands has been in top 5 list for 7 of last 12 days. Montana has been in top 5 list for 61 of last 126 days. Wyoming has been in top 5 list for 111 of last 226 days. Guam has been in top 5 list for 18 of last 32 days.

Hawaii, Louisiana, Maine, and South Carolina did not report active cases. Several states have stopped posting new case and new death numbers. I will back calculate where possible.

A column on the right shows the current growth rate divided by the 5 day moving average. New Mexico, Rhode Island, South Dakota, Navajo Nation, and Federal Prisons were over 2.0 yesterday (red highlight). Arkansas, Guam, Idaho, Montana, and Nevada were over 1.5 yesterday (yellow highlight). This is an early warning of higher growth rate in states. Many states now do not report every day making this measure more variable for those states.

My calculated growth rate for USA is 0.00629 for yesterday, up from previous day of 0.00590. This is not population or case number weighted.

Daily active case counts have a notable decline over the last couple months. The number of active cases have dropped about 25% since the peak. This decrease in active case numbers had not been seen since I started recording information in February 2020.

Volvolugnut

[volvolugnut]

More statistics on US states and COVID-19 growth rates. My raw information is from Worldometer. Any errors or misrepresentations are my own.

These tables show all available US states and territories and the COVID-19 data for the last 5 days. I have sorted the states alphabetically and added growth rates for last several days for all states with ranking of each day. Of course, this information changes daily. I have presented the table in two parts because of the screen shot, but it is actually one table in Excel.

Again, results change daily.

State growth rates for May 5, 2020. All information is based on reported information and actual results may be different.

For your information, the top 5 states or territories yesterday in growth rate (the worst containment) are: US Virgin Islands (0.464) with 3178 cases, North Dakota (0.175) with 108,081 cases, Wyoming (0.155) with 58,438 cases, Arkansas (0.142) with 336,760 cases, and Montana (0.120) with 109,455 cases. US Virgin Islands has been in top 5 list for 8 of last 13 days. North Dakota has been in top 5 list for 195 of last 307 days. Wyoming has been in top 5 list for 112 of last 227 days. Arkansas has been in top 5 list for 116 of last 258 days. Montana has been in top 5 list for 62 of last 127 days.

Hawaii, Louisiana, Maine, and South Carolina did not report active cases. Several states have stopped posting new case and new death numbers. I will back calculate where possible.

A column on the right shows the current growth rate divided by the 5 day moving average. Arkansas, Kansas, New Mexico, North Carolina, Oklahoma, Rhode Island, Tennessee, US Virgin Islands, US Military, and Federal Prisons were over 2.0 yesterday (red highlight). Idaho, Nevada, and New Jersey were over 1.5 yesterday (yellow highlight). This is an early warning of higher growth rate in states. Many states now do not report every day making this measure more variable for those states.

My calculated growth rate for USA is 0.00687 for yesterday, up from previous day of 0.00629. This is not population or case number weighted.

Daily active case counts have a notable decline over the last couple months. The number of active cases have dropped about 25% since the peak. This decrease in active case numbers had not been seen since I started recording information in February 2020.

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